1. Field of the Invention
This invention relates to an optical communication package such as optical transmitter and receiver modules and, particularly, to an optical communication package with lock mechanism detachable to a cage.
2. Description of the Related Art
FIG. 1 is a perspective view showing a conventional optical communication package 40 in state of being attached to a communication device 41 (e.g., U.S. Pat. No. 6,439,918 B1). The package 40 is disposed between an optical fiber (not shown) and the communication device 41 to send optical signal received form the optical fiber to the communication device 41 while converting it into electrical signal, or to send electrical signal received from the communication device 41 to the optical fiber while converting it into optical signal. The package 40 has a socket 5 to allow the optical fiber to be detachably connected thereto and is detachable to the communication device 41 in order to address a case that internal optical and electrical elements has a problem or a case that its communication specifications (optical wavelength, modulation method etc.) are required to conform to those of the other party.
FIG. 2 is a perspective view showing the conventional optical communication package 40 in state of being locked in a cage 2. The package 40 is detachably inserted into the cage 2 mounted on a board 42 in the communication device 41 and is releasably locked by the cage 2. The cage 2 is shaped like a long box extended backward and forward and has an opening at one end (front end), such that the package 40 can be inserted or extracted through the front end. The cage 2 has nails 6 on both sides so as to engage with the internally-inserted package 40 to restrict the movement of package 40 in the extraction direction. The nails 6 are formed like a leaf spring that protrudes inside the cage 2 at the sides and extends backward.
FIG. 3 is a perspective view showing the conventional optical communication package 40 in state of being extracted from the cage 2. FIG. 4 is an enlarged perspective view showing part of the package 40 in FIG. 3. FIG. 5 is an enlarged partially sectioned perspective view showing a locking portion 43 of the package 40 in state of being locked by a nail 6 of the cage 2. FIG. 6 is an enlarged partially sectioned perspective view showing the locking portion 43 in state of being unlocked from the nail 6.
As shown in FIGS. 3 to 5, the package 40 is provided with the locking portion 43 to be engaged with the nail 6 of cage 2 and a release mechanism 44 to release the engagement of locking portion 43 and nail 6. The locking portion 43 corresponds to the back end face of a recess 7 provided on both sides of package body 45, and contacts the free end (back end) of nail 6 being entered into the recess 7. The release mechanism 44 is composed of a slide member 46 that is backward and forward slidably attached to the package body 45 and has a taper 12 to push out the nail 6 from the inside of recess 7. The slide member 46 includes a handle 47 that is located on the front side of package body 45 and extends rightward and leftward. By pulling the handle, the taper 12 is slid into the recess 7. Then, as shown in FIGS. 5 and 6, with the taper 12 being slid into the recess 7, the nail 6 is put out of the recess 7.
The communication device 41, as shown in FIG. 1, has a plurality of openings 48 to each of which package 40 is attached, so that multiple optical fibers can be connected thereto in clumps. Thus, the openings 48 are disposed close to each other on multiple stages formed upward and downward to house packages 40 in clumps.
Since the openings 48 of communication device 41 are disposed close to each other and the handles 47 are closely on the front face so as not to interfere with the connection of optical fiber in the package 40 being locked in the cage 2, the handle 47 is difficult to hold. Further, the release of locking is difficult since the pulling of handle 47 meets resistance from the nail 6.
Further, since the package 40 is drawn out due to friction when the handle 47 is pulled, malfunction may occur in the case that the nails 6 on both sides cannot be simultaneously pushed out from the recesses 7. Thus, in some cases, the handle 47 cannot be taken out easily.